4.  That the root of the Hairs were pretty smooth, tapering inwards, almost like a Parsneb; nor could I find that it had any filaments, or any other vessels, such as the fibres of Plants.

5.  That the top when split (which is common in long Hair) appear’d like the end of a stick, beaten till it be all flitter’d, there being not onely two splinters, but sometimes half a score and more.

6.  That they were all, as farr as I was able to find, solid Cylindrical bodies, not pervious, like a Cane or Bulrush; nor could I find that they had any Pith, or distinction of Rind, or the like, such as I had observ’d in Horse-hairs, the Bristles of a Cat, the Indian Deer’s Hair, &c.

Observations on several other sorts of Hair_._

For the Brisles of a Hogg, I found them to be first a hard transparent horny substance, without the least appearance of pores or holes in it; and this I try’d with the greatest care I was able, cutting many of them with a very sharp Razor, so that they appear’d, even in the Glass, to have a pretty smooth surface, but somewhat waved by the sawing to and fro of the Razor, as is visible in the end of the Prismatical body A of the same Figure; and then making trials with causing the light to be cast on them all the various ways I could think of, that was likely to make the pores appear, if there had been any, I was not able to discover any.

Next, the Figure of the Brisles was very various, neither perfectly round, nor sharp edg’d, but Prismatical, with divers sides, and round angles, as appears in the Figure A. The bending of them in any part where they before appear’d cleer, would all flaw them, and make them look white.

The Mustacheos of a Cat (part of one of which is represented by the short Cylinder B of the same Figure) seem’d to have, all of them that I observ’d, a large pith in the middle, like the pith of an Elder, whose texture was so close, that I was not able to discover the least sign of pores; and those parts which seem to be pores, as they appear’d in one position to the light, in another I could find a manifest reflection to be cast from them.

This I instance in, to hint that it is not safe to conclude any thing to be positively this or that, though it appear never so plain and likely when look’d on with a Microscope in one posture, before the same be examin’d by placing it in several other positions.

And this I take to be the reason why many have believed and asserted the Hairs of a man’s head to be hollow, and like so many small pipes perforated from end to end.

Now, though I grant that by an Analogie one may suppose them so, and from the Polonian disease one may believe them such, yet I think we have not the least encouragement to either from the Microscope, much less positively to assert them such.  And perhaps the very essence of the Plica Polonica may be the hairs growing hollow, and of an unnatural constitution.